Flexural bearings are used to provide a linear range of rotation versus torque to enable precision engineering, pointing, and control. Many applications involve a primary modal frequency. If multiple parts are vibrating at the primary modal frequency, damage can occur to the parts. Existing flexure bearings provide a constant rotational stiffness, which requires high fidelity design in order to meet specific modal frequency requirements.
A flexure bearing is typically made of metal and has a geometry that permits a low stiffness in one degree of freedom and high stiffness in all others. Flexure bearings can be made of a solid piece of metal that has been cut into the flexure bearing shape. There are a number of companies that sell flexure bearing products, such as C-Flex, of Frankfort, N.Y. Tunable modal frequency devices, such as those sold by Minusk K Technology, of Inglewood, Calif., currently employ mechanisms to change the frequency of the bearing. These devices require manual or motor driven methods. In operation, flexure blades may be used to reduce the line-of-sight jitter (or pointing error) of a telescope that is associated with rotational positioning of a telescope.